Safety cabinet

ABSTRACT

A safety cabinet has a body adapted to contain hazardous substances and having an upright front side, a base underneath the cabinet and adapted to support the cabinet spaced above an underlying floor. The base having an upright front wall below the body, set back from the front side thereof, and formed with a plurality of air intake openings, and structure in the base forming a suction-vent passage extending from the intake openings.

FIELD OF THE INVENTION

The present invention relates to a cabinet. More particularly this invention concerns a safety cabinet for the storage of hazardous substances.

BACKGROUND OF THE INVENTION

Such a cabinet is described, for example, in German utility model DE 297 18 687. It is made of sheet metal primarily intended and suited for holding electronic devices. In this cabinet, the housing is formed by two side walls and a lid that form the body. In this manner, an intermediate space is implemented, in which at least one fan can be provided. This concept has proven itself.

Totally aside from this, so-called cable distributor cabinets are known, as described in detail in DE 1 910 585. Such cable distributor cabinets are equipped, in most cases, with a cavity between an inner wall and an outer wall, to guide intake air, in order to be able to conduct away heat generated in the interior.

Independent of this, so-called undercounter cabinets of the applicant, called “UTS Line,” are available commercially. These undercounter cabinets have permanent floor exhaust ventilation through a slotted base. In this manner, harmful substances or vapors that collect on the floor are safely taken up and passed to the exhaust air, if necessary.

The prior-art systems are not satisfactory in all aspects. For example, the bases of the known cabinets are a problem, for example when removing objects or chemicals stored in them. This is particularly true for the case when they are implemented as so-called undercounter cabinets, and an operator is working above these cabinets.

It is true that there are already approaches, in the state of the art and fundamentally, to the effect of equipping a cabinet with a base that is set back, as described in DE 629 24 781, for example. However, the cabinets described there are not safety cabinets, in other words cabinets that meet certain safety requirements; instead, a cabinet carcase is described that serves in particular to accommodate electrical equipment. Furthermore, the stability of the known cabinets requires improvement. This is where the invention, as a whole, wishes to provide an improvement.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide an improved safety cabinet.

Another object is the provision of such an improved safety cabinet that overcomes the above-given disadvantages, in particular that use is facilitated and, at the same time, particularly great stability is achieved.

SUMMARY OF THE INVENTION

A safety cabinet has according to the invention a body adapted to contain hazardous substances and having an upright front side, a base underneath the cabinet and adapted to support the cabinet spaced above an underlying floor. The base having an upright front wall below the body, set back from the front side thereof, and formed with a plurality of air intake openings, and is structure in the base forming a suction-vent passage extending from the intake openings.

The air intake openings according to the invention can extend along a lower edge of the front wall, in other words can be provided at the lower edge of the front wall. This orientation particularly takes the circumstance into account that harmful substances or vapors that are heavier than the ambient air collect on the floor, and can be reliably taken up by these air intake openings and exhausted.

In fact, the cabinet is a safety cabinet that is suitable for accommodating substances and materials that are at risk of explosion, such as chemicals, for example. For this purpose, the cabinet normally has a special wall structure, with an outer body made of sheet steel, so that fire resistance values of 90 minutes or even more can easily be achieved.

Optimal exhaust ventilation of possible harmful substances or vapors, in general, in the floor region, is additionally taken into account in that the intake air openings are advantageously configured as longitudinally elongated slots. In this connection, the longitudinal extent of the longitudinal slots coincides with the longitudinal extent of the front wall, so that the air intake openings form a large air intake cross-section extending the full length of the lower edge of the set-back front wall.

In this connection, the base front wall that is set back relative to the base side walls ensures that at the same time, handling and any work on or above the cabinet can be carried out in particularly advantageous manner. This is because the cabinet is generally a base cabinet or so-called undercounter cabinet, in other words a cabinet that is generally designed to be placed below a counter, a sink, etc.

Because, according to the invention, the base front wall is set back relative to the base side walls, which project to the side an operator can step up flush to the front of the cabinet. This is because the set-back base front wall essentially makes a clear space available for the operator's toes so that the operator can step practically right up to a counter, a sink, etc. above the cabinet. Within the scope of the invention, this is made possible in that the base front wall is set back relative to the projecting base side walls, specifically by an amount that corresponds to half the foot length of an adult. A set-back in the range between 10 and 20 cm, up to as much as 30 cm, results from this. At the same time, the base side walls, which project at each end past the front wall in contrast ensure that the stability of the cabinet, i.e. the lower cabinet or undercounter cabinet, is not impaired. In other words, the cabinet in question cannot tip over forward front when doors, drawers, or inserts that are provided on the front are opened.

In this connection, it has furthermore proven to be advantageous if the base is releasably connected with the body. This is because in this manner, different base heights, different base designs, etc. can be used. It is also possible to mount casters on the base, in order to make the cabinet as a whole movable. This guarantees that exhaust ventilation in the floor region in front of the cabinet or underneath even the lowest pulled-out drawer is maintained. This is because the intake air openings are provided in the set-back base front wall, specifically at a lower edge of the base front wall.

The design as a whole is such that the one or more air intake openings communicate with one or more exhaust air openings. This exhaust air opening is in or on a rear wall of the body. An exhaust air (ventilation) unit can be connected with this exhaust air opening or openings for continuous exhaust ventilation. An exhaust blower can be provided on each cabinet, or a central exhaust blower for a laboratory or an area of a laboratory can for example be connected to a plurality of such cabinets.

It is recommended to monitor exhaust air monitoring with a sensor. The sensor can determine whether or not the stream of the exhaust air is present, in accordance with the requirements, either continuously or at specific predetermined time intervals. The sensor can furthermore be connected with an optical and/or acoustical alarm triggered when deviations from the predetermined volume stream of the exhaust air are observed.

The one or more exhaust air openings can be provided on the downstream end of one or more air shafts. These air shafts are generally situated on or in the rear wall of the body. In this connection, the air shafts are usually closed because they routinely serve to guide the intake air that has been drawn in by way of the intake air openings through the body of the cabinet, all the way to the exhaust air opening. Fundamentally, however, supplemental openings can also be provided in the air shafts, in order to also vent the interior of the cabinet, i.e. the body.

In this connection, the design of the individual air shaft is such that the air shaft extends all the way into a body bottom on the suction side, and thereby communicates with the air intake opening. In fact, the base is designed to be predominantly closed, except for the one or more air intake openings, so that air that enters the base by way of the intake openings flows through the base and then enters the air shaft that extends all the way to the body bottom. After the intake air has exited the air shaft it enters the one or more exhaust air openings, i.e. to the suction side of the exhaust blower connected to them, which blower provides the required partial vacuum and the flow described using a fan or a comparable suction unit.

Since the cabinet is predominantly a safety cabinet, a cabinet door is normally equipped with a self-locking mechanism having a thermal fuse. The thermal fuse ensures that the cabinet door is automatically locked at a high temperature, generally 60° C. or more than 80° C., so that, in case of a fire, chemicals or other substances at risk of explosion are protected from any open flame or overly high temperatures. A comparable self-locking mechanism having a thermal fuse can also be used for a drawer or an insert. Here, the invention takes the circumstance into account that the cabinet is configured as a drawer cabinet and/or insert cabinet with an additional cabinet door or multiple additional cabinet doors, if necessary.

In all cases, a cabinet, particularly a safety cabinet, and very particularly a safety cabinet that is a base or undercounter cabinet is provided that allows particularly advantageous and functionally appropriate operation. This is because the set-back base front wall ensures that an operator can step practically right up to a table, a sink, etc. above the cabinet. This is because the clear space created by the set-back base front wall in the region of the base can be utilized by the operator's feet, so as to be able to step right up in front of the cabinet or a work counter placed above it.

At the same time, the base side walls that project to the side, relative to the set-back base front wall, ensure that the stability of the cabinet is unchanged. This is particularly significant when the cabinet is has drawers cabinet and/or pull-out inserts, and that bottles of chemicals, for example, which have a weight that is not insignificant, are stored in its interior. The projecting base side walls now ensure that the cabinet according to the invention cannot tip over even when the is individual drawers or inserts are pulled out.

At the same time, special safety aspects are taken into consideration, because vapors or hazardous substances, in general, that collect at the floor are continuously and reliably drawn off by way of the intake air openings situated in the set-back base front wall. These are the significant advantages.

BRIEF DESCRIPTION OF THE DRAWING

The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a perspective view of the cabinet according to the invention, when open;

FIG. 2 is a partial perspective view showing the cabinet when closed; and

FIG. 3 is a partly schematic vertical section through the cabinet according to the invention.

SPECIFIC DESCRIPTION

As seen in FIGS. 1 and 2 a safety cabinet according to the invention has, among other things, a specific fire resistance (for example fire resistance class 90), largely due to a sheet-metal jacket, and generally is used to store chemicals or other substances at risk of explosion. The cabinet is a base or undercounter cabinet, and for this purpose is underneath a laboratory table 1 or, in general, a work counter 1. In place of the laboratory table 1, a sink, a cabinet, or some other superstructure can also be provided above it.

The base cabinet as shown here is configured as a combined drawer and door unit, but of course this is not to be understood as being restrictive. The illustrated cabinet has a one or more pull-out drawers 2 covered by a left-hinged door 3 on the left and on the right has a single big drawer 4 with a vertical front. The door 3 and the drawer front 4 are both relatively massive and solidly close the front of the cabinet 1.

The cabinet is basically comprised of a body 5 sitting atop a base 6. The body 5 and the base 6 are releasably connected with one another, so that other bases 6 than the one shown can also be combined with the body 5, for example a base 6 having casters or one that has taller or shorter.

The base 6 has air intake openings 7 by way of which air 8 drawn into the base 6 and passes along an air passage or shaft 9 extending underneath and then up the back of the body 5, all the way to an exhaust opening 10 connected to the suction side of a blower 11. The partial vacuum required for the flow as described is produced using the exhaust blower 11. Furthermore, the exhaust blower 11 can be equipped with a sensor that monitors the exhaust air stream and/or intake air stream, as described above.

The upper wall of the horizontal lower leg of the air shaft 9 is a lower wall or floor 5 a of the base 6 while the vertical leg of the air shaft 9 is defined between the rear wall 5 b of the base 6 and an inner partition 12 as shown by the arrows in FIG. 3. As a result, any vapors or harmful substances that collect on the floor in front of the cabinet 1 are reliably drawn away from this floor region.

When comparing FIGS. 2 and 3, it becomes clear that the air intake openings 7 are provided in a vertical base front wall 6 a that is set arrangement relative to the vertical base side walls 6 b that therefore project to the at ends of the cabinet past the front wall 6 a. In this way, the two base side walls 6 b that project to the side, in combination with the set-back base front wall 6 a, form a forwardly open cavity 13 whose depth T, in accordance with the representation in FIG. 3, corresponds to about half a foot length of an adult, in other words lies in the range between 10 cm and 30 cm. In other words, this clear space 13 forms a toe space or setback for operator comfort, so that the operator can step practically right up to the front of the cabinet, i.e. the body 5, and also right up to the work counter 1.

It can be seen that the air intake openings 7 are provided on a lower edge of the set-back base front wall 6 a and are elongated horizontally parallel to this lower edge. Furthermore, the horizontally elongated air intake openings or slots 7 are distributed along the full horizontal length of the set-back front wall 6 a.

Finally, the cabinet door 3 as well as the insert 4 and, if applicable, the one or more drawers 2, are also equipped with a self-locking mechanism having a thermal fuse. Starting from a certain temperature (for example more than 60° C. or more than 80° C.), the thermal fuse is triggered, and the locking mechanism ensures that the cabinet door 3, the drawer 2, and the insert 4 are automatically locked, so that chemicals or substances that are at risk of explosion, in general, are protected from an open flame or overly high temperatures. 

1. A safety cabinet comprising: a body adapted to contain hazardous substances and having an upright front side; a base underneath the cabinet and adapted to support the cabinet spaced above an underlying floor, the base having an upright front wall below the body, set back from the front side thereof, and formed with a plurality of air intake openings; and structure in the base forming a suction-vent passage extending from the intake openings.
 2. The safety cabinet defined in claim 1 wherein the air-intake openings are distributed in a horizontal row along the base front wall.
 3. The safety cabinet defined in claim 2 wherein the openings are horizontally elongated slots.
 4. The safety cabinet defined in claim 1 wherein the base and body are separable from each other.
 5. The safety cabinet defined in claim 1 wherein the openings communicate with an exhaust opening on a back wall of the body.
 6. The safety cabinet defined in claim 5 wherein the body is formed in the back wall with an air passage.
 7. The safety cabinet defined in claim 6 wherein the passage extends from the back wall and through the base to the openings.
 8. The safety cabinet defined in claim 5, further comprising an exhaust blower having a suction side connected to the exhaust opening.
 9. The safety cabinet defined in claim 1 wherein the cabinet has at least one drawer.
 10. The safety cabinet defined in claim 1 wherein the cabinet has at least one hinged door.
 11. The safety cabinet defined in claim 10 wherein the hinged door has a thermal lock that latches the door when heated above a predetermined temperature.
 12. The safety cabinet defined in claim 1 wherein the body has side and end walls of fire-resistant construction.
 13. The safety cabinet defined in claim 12 wherein the base has side walls the project forward past the front wall so as to have front edges vertically generally aligned with the front side.
 13. A safety cabinet comprising: a hollow body adapted to contain hazardous substances and having an openable front side; a base underneath the cabinet and adapted to support the cabinet spaced above an underlying floor, the base having an upright front wall below the body, set back from the front side thereof, and formed with a plurality of air intake openings; and structure in the base forming a suction-vent passage extending horizontally from the intake openings horizontally underneath the body and up a back side of the body to an exhaust opening on the back side of the body; and an exhaust blower having a suction side connected to the exhaust opening. 